Research And Production Of High-Speed Railway Sleeper Screw

This paper does some researches on the raw material of high-speed railway sleeper screw met production inquirement, designs appropriate production process and equipments, and relative testing instruments. The raw material, thread rolling and testing instrument are the innovation work of the paper.Firstly, on the basis of clearing out the design objective, TD16 is developed according to technology inquirement of sleeper screw. Its smelting process is EAF/BOF+ LF+VD/RH+CCM. Metallurgical structure is ferrite plus pearlite. Yield strength is up to 325Mpa, tensile strength is 500～640 Mpa, elongation strain is 25%. TD16 provides guarantee for production of screw spike.Secondly, a appropriate production process is designed through many test and comparison:acid-washing of steel wire rod, wire drawing, cutting and forming, heading, cutting-edge, thread rolling, assembling filling piece and hot-dip in sequence. Sleeper screw is produced by hot thread rolling. This process is the most important parts of production, and is the key point of research. In this paper the principle of thread rolling, heating, the parameters of thread rollig and threading roller. By experiment and comparison,the heating temperature is up to 1150～1200℃. The threading roller is made of SKD61. As for the parameters of thread rolling, threading force, velocity and amount of feed are discussed in the paper.Thirdly, in order to test production conveniently, screw pitch caliper, screw GoNo go gauge, measurement tool of inside diameter and straightness accuracy are designed.Finally, the research conclusion and suggested improvements are given.The paper is combined closely with application. This kind of sleeper screw have applied for WU-GUANG high-speed railway successfully, and make contribution to railway construction and locomotive safe running. In the course of application, it meets the design requirement. The quality of sleeper screw is the same as like products of home and abroad.